The present invention relates to electrical terminations and, in particular, to a "twist-on" type of connector terminal which non-permanently mounts to one or more conductors for electrically joining the conductors and making an electrical connection to a variety of termination points without undue time and conductor preparation.
Electrical terminations can be created in various fashions. A rudimentary connection can be achieved by merely touching or securing an exposed end of a conductor to an appropriate connection, such as by fastening an exposed conductor beneath a screw or inserting the conductor end into a mating fastener. Frequently, multiple conductors are spliced together, for example, by twisting or soldering exposed ends together before covering the joint with tape, shrink tubing or another electrically insulating cover.
A "twist-on" connection is commonly used to electrically join or splice multiple conductors within an insulated housing. Depending upon the type of twist-on wire, the conductors can be secured to the housing with screw fasteners or can be directly screwed to the housing to compress the conductor ends together. Many twist-on wire connectors contain a spiral wound spring that expands to secure the conductors together under compression. A variety of twist-on wire connectors of differing constructions are commercially available, but all of which merely connect a number of twisted wires together without accommodating a further connection to a terminal. Such other terminal may also require a custom terminal end.
The latter type of connection is frequently required when it is necessary to connect multiple conductors to a single, common termination point, such as when making control circuit connections. One solution is to connect the individual conductors to a terminal strip and from which a conductor having an appropriate termination end can be routed to the termination point. Multiple conductors can also be spliced together with a custom prepared pigtail having an appropriate terminal end. An oversized connector terminal having an appropriate terminal end may also be secured to a number of conductors. Such connector terminals frequently require the conductors to be secured with solder or included crimp or screw fasteners. In all cases, an appreciable amount of time is required to prepare a custom termination from a number of parts that are specially adapted to the particular wiring problem.
A connector terminal which addresses the foregoing problem is disclosed in U.S. Pat. No. 5,531,618 and wherein a twist-on type of terminal connector is disclosed. A conical, spiral wound spring is provided at the connector to permit a twist mounting to one or more conductors. The connector terminals include a variety of termination ends, which are permanently secured to an internal spring. Electrical continuity between the spring and terminal end is obtained, for example, by brazing or soldering the terminal end directly to the spring. Terminal ends extending from integral springs are also suggested. Either alternative provides suitable electrical continuity, although the alternative used can affect the cost of the finished connector terminal.
The present invention provides connector terminals wherein a discrete terminal fitting and spring provide an improved fastening between the spring and termination end. A durable connection is made, which assures electrical continuity and which can be readily effected in a high volume manufacturing setting.
A variety of types of terminal ends are particularly disclosed wherein various terminal ends include a collar and from which a number of prongs extend. The prongs are fitted to grooves at a housing molded from an appropriate electrical insulator and flared or staked to the housing. A tapered spring, in turn, is fitted to the housing to create a permanent, non-removable connection between the terminal end, spring and housing.